As a speaker apparatus for preventing abnormal sound generated by entry of iron powder or magnetic powder into a magnetic gap, a speaker indicated in Patent Literature 1 has been proposed. The speaker of Patent Literature 1 includes a through-hole extending through a magnetic circuit at the center of the bottom surface of the magnetic circuit of the speaker. Iron powder or magnetic powder passes through a central hole formed through a frame and enters a through-hole of a yoke. Thus, abnormal sound generated by entry of iron powder or magnetic powder into a magnetic gap is prevented.
However, in a place where there is a lot of sand, the aforementioned dust measure is insufficient, and there is a risk that the dust enters the magnetic gap through an air hole of the yoke, resulting in drive failure.